I noticed yesterday as I walked away from my car that the auto alarm and door locks did not work.The keypad will lock and un-lock the doors,but the alarm fails to arm,you normally hear a chirp when you close the door.Also whenever you lock or un-lock the doors you arm and disarm the alarm,this is not working.Is it possible I hit something by accident or is it a faulty relay etc.If I hold the keypad for a few seconds the alarm will go off,but I still want the alarm to arm itself on its own.Any help will be greatly appreciated.

 

Aftermarket alarm or GM factory alarm?

If aftermarket, back to installer. Most aftermarket alarm installs are hokey and troublesome.